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Guide

The 183-Day Rule for US Digital Nomads: Foreign Tax Residency on Top of US Worldwide Tax

Each country runs its own tax residency test, and none of them changes the fact that the US taxes its citizens on worldwide income. This guide sets the foreign day counts against the IRS 330-day test and shows how to plan a year around both.

Alfama rooftops and the Tagus River, Lisbon, Portugal, seen from the Miradouro de Santa Luzia. Used as the home page hero.
Photo by Ввласенко, CC BY-SA 4.0, via Wikimedia Commons

Published: 2026-10-16 · Last verified: 2026-10-16 · Numbers apply to US passport holders

Rules change. Confirm the current rules with the official sources linked below before you apply, pay a fee, or book travel around a date in this guide.

Two tax systems, two clocks

US citizens are taxed on their worldwide income no matter where they live, and they have the same filing requirements as citizens living in the United States (IRS Publication 54). Becoming a tax resident somewhere else does not switch off US tax. It gives a second country a claim on your income too. Estonia, Colombia and Germany tax their residents on worldwide income. Thailand taxes residents on Thai-source income and on foreign-source income brought into Thailand.

The US offers two main ways to avoid paying tax twice. The first is the foreign earned income exclusion (FEIE), capped at $132,900 per person for tax year 2026, or $11,075 per month. The second is the foreign tax credit, claimed on Form 1116, for foreign income tax paid on income you did not exclude under the FEIE. You only get either one if you file a US return.

There is no single 183-day rule

"183 days" is shorthand. The real tests differ in the threshold, in the window they measure, and in whether they also look at something other than days:

Three of these tests use rolling windows (Portugal, Estonia, Colombia). Two use the calendar year (Spain, Thailand). Malaysia uses the basis year, and Germany does not count days at all. If you split your year to stay under a calendar-year test, a rolling-window test can still catch you.

The US day count: 330 of 365

For most nomads, the FEIE depends on the physical presence test. You need 330 full days in a foreign country or countries during any 12 consecutive months. The window can start on any date. In a 365-day window that leaves 35 days you can spend in the US or anywhere that is not a foreign country. Publication 54 also requires your tax home to be in a foreign country, so day counts alone do not qualify you.

So the planning problem is this: you need about 330 days abroad for the US exclusion while keeping each country's count under its own threshold. A partial travel day can count toward Colombia's total, because Colombia counts entry and exit days, but it is not a full day for the 330. Keep a dated log of every border crossing.

Day-count strategies by country

A worked year

One way to plan 365 days: 85 days in Portugal, then 90 days in Colombia, then 85 days in Spain, then 90 days in Malaysia, plus 15 days in the US. That is 350 days abroad, which clears 330, and 15 US days, which is under the 35-day allowance. The 90 days in Colombia sit between the two Schengen blocks, so neither block breaks the 90 in 180 rule. Each country stays under its threshold: 85 is under 183 in Portugal and Spain, 90 is under 183 in Colombia, and 90 is under 182 in Malaysia.

Even so, this year has limits:

When crossing the line is the better choice

Becoming a tax resident is not automatically worse. If you pay local income tax, you may be able to credit it against US tax on the same income. Estonia and Germany each have a tax treaty with the US, and the Germany treaty can reassign residence if both countries claim you. Long-term residence routes also need years of real residence. Portugal and Spain each require 5 years, and Estonia's long-term resident permit requires 5 years on a temporary residence permit. Those years usually come with tax residency.

Before you apply

Thresholds, visa terms and the FEIE cap change, and the FEIE cap is adjusted every year. Before you book a year around these numbers, check each one with the official source listed below for that country and with IRS Publication 54. If your plan depends on landing just under a threshold, get a written opinion from a tax adviser who handles both the US and the country in question.

Country pages

Official sources

Facts in this guide last verified against the sources: 2026-10-16